/Engine/Source/Runtime/GameplayTags/Classes/GameplayTagContainer.h
If a Tag with the specified tag name explicitly exists, it will remove that tag and return true. Otherwise, it returns false. It does NOT check the TagName for validity (i.e. the tag could be obsolete and so not exist in the table). It also does NOT check parents (because it cannot do so for a tag that isn't in the table). NOTE: This function should ONLY ever be used by GameplayTagsManager when redirecting tags. Do NOT make this function public!
bool RemoveTagByExplicitName ( const [FName](API\Runtime\Core\UObject\FName) & TagName )